1. Field of the Invention
The present invention relates to an improved fan structure, and in particular, to a fan structure having a shining effect.
2. Description of Prior Art
With the development of modern information technology, in addition to inherent functions of the electric products, manufacturers continuously update and improve the primary performance and additional functions, and even develop various multiple-function products so as to satisfy the demands of customers. Such kind of versatile products are available and striking in the market so as to attract the attention of the customers and cause them to purchase.
However, owing to the violent competition in the market, products and the functions thereof developed by each manufacture are substantially the same, and thus simple improvements in functions are not attractive enough to the customers. Therefore, since the most important demands of the customers are novelty, variation and distinctive features, all the manufactures start to change the originally monotonous and old-fashioned designs, and adopt shining appearances to attract the attention of young generation.
As a result, in view of the above concept, there are more and more computer casings having avant-garde styles everywhere in the market. Especially, a transparent casing by which the internal elements can be clearly seen has broken the traditional designs and raised a trend of transparency, causing all the manufactures to successively imitate this design. Thereafter, light-emitting elements (e.g. LED) are further arranged in the periphery of the computer casing or associated with other components (e.g. hard disc) to produce shining effect by using simple control circuits, which completely change the stiff and dull image of the electric products.
Under such a trend of breaking tradition, heat-radiating fans are also modified to change their inherent stiff designs. There are various kinds of structures in existing heat-radiating fans having light-emitting devices. For example, a conventional fan is provided with a light source in rear of the fan blades. When the blades are rotating, the light source can be blocked by the rotating blades, causing a twinkling visual effect. Further, in another conventional art, a plurality of light-emitting elements are incorporated into a soft circuit board, and then the circuit board is provided on each blade. A timing control circuit controller is provided to successively control each light-emitting element. When the blades rotate, predetermined patterns or characters can be displayed on the blades owing to the persistence of vision of human being.
In the above conventional art, the light-emitting elements are arranged according to predetermined patterns or characters, and positioned on the front or back of the blades. Next, by controlling with a circuit board, a shining effect can be produced. Further, the connected electrodes or circuits can be suitably hidden without affecting the aesthetic appearance of the heat-radiating fan. However, in order to suitably hide the electrodes or circuits, the production cost and complexity of the fan will be inevitably increased. Further, arranging the light-emitting elements on a base (e.g. blade) has to additionally mount a fixing base, which increases the total weight of the blades and affects the rotating performance of the heat-radiating fans. If the light-emitting elements are provided in front of the blades, connecting the electrodes directly to the front of the blades will affect the external appearance of the heat-radiating fan, and the exposed electrodes will easily interfere with the normal rotation of the blades. Thus, the conventional arts indeed have some problems.